diff options
Diffstat (limited to 'fs/open.c')
| -rw-r--r-- | fs/open.c | 97 |
1 files changed, 66 insertions, 31 deletions
diff --git a/fs/open.c b/fs/open.c index 182d8667b7b..9b33c0cbfac 100644 --- a/fs/open.c +++ b/fs/open.c @@ -61,33 +61,22 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, return ret; } -static long do_sys_truncate(const char __user *pathname, loff_t length) +long vfs_truncate(struct path *path, loff_t length) { - struct path path; struct inode *inode; - int error; - - error = -EINVAL; - if (length < 0) /* sorry, but loff_t says... */ - goto out; + long error; - error = user_path(pathname, &path); - if (error) - goto out; - inode = path.dentry->d_inode; + inode = path->dentry->d_inode; /* For directories it's -EISDIR, for other non-regulars - -EINVAL */ - error = -EISDIR; if (S_ISDIR(inode->i_mode)) - goto dput_and_out; - - error = -EINVAL; + return -EISDIR; if (!S_ISREG(inode->i_mode)) - goto dput_and_out; + return -EINVAL; - error = mnt_want_write(path.mnt); + error = mnt_want_write(path->mnt); if (error) - goto dput_and_out; + goto out; error = inode_permission(inode, MAY_WRITE); if (error) @@ -111,19 +100,40 @@ static long do_sys_truncate(const char __user *pathname, loff_t length) error = locks_verify_truncate(inode, NULL, length); if (!error) - error = security_path_truncate(&path); + error = security_path_truncate(path); if (!error) - error = do_truncate(path.dentry, length, 0, NULL); + error = do_truncate(path->dentry, length, 0, NULL); put_write_and_out: put_write_access(inode); mnt_drop_write_and_out: - mnt_drop_write(path.mnt); -dput_and_out: - path_put(&path); + mnt_drop_write(path->mnt); out: return error; } +EXPORT_SYMBOL_GPL(vfs_truncate); + +static long do_sys_truncate(const char __user *pathname, loff_t length) +{ + unsigned int lookup_flags = LOOKUP_FOLLOW; + struct path path; + int error; + + if (length < 0) /* sorry, but loff_t says... */ + return -EINVAL; + +retry: + error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); + if (!error) { + error = vfs_truncate(&path, length); + path_put(&path); + } + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } + return error; +} SYSCALL_DEFINE2(truncate, const char __user *, path, long, length) { @@ -306,6 +316,7 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode) struct path path; struct inode *inode; int res; + unsigned int lookup_flags = LOOKUP_FOLLOW; if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */ return -EINVAL; @@ -328,8 +339,8 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode) } old_cred = override_creds(override_cred); - - res = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path); +retry: + res = user_path_at(dfd, filename, lookup_flags, &path); if (res) goto out; @@ -364,6 +375,10 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode) out_path_release: path_put(&path); + if (retry_estale(res, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } out: revert_creds(old_cred); put_cred(override_cred); @@ -379,8 +394,9 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename) { struct path path; int error; - - error = user_path_dir(filename, &path); + unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY; +retry: + error = user_path_at(AT_FDCWD, filename, lookup_flags, &path); if (error) goto out; @@ -392,6 +408,10 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename) dput_and_out: path_put(&path); + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } out: return error; } @@ -425,8 +445,9 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename) { struct path path; int error; - - error = user_path_dir(filename, &path); + unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY; +retry: + error = user_path_at(AT_FDCWD, filename, lookup_flags, &path); if (error) goto out; @@ -445,6 +466,10 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename) error = 0; dput_and_out: path_put(&path); + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } out: return error; } @@ -489,11 +514,16 @@ SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, umode_t, mode { struct path path; int error; - - error = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path); + unsigned int lookup_flags = LOOKUP_FOLLOW; +retry: + error = user_path_at(dfd, filename, lookup_flags, &path); if (!error) { error = chmod_common(&path, mode); path_put(&path); + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } } return error; } @@ -552,6 +582,7 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user, lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; if (flag & AT_EMPTY_PATH) lookup_flags |= LOOKUP_EMPTY; +retry: error = user_path_at(dfd, filename, lookup_flags, &path); if (error) goto out; @@ -562,6 +593,10 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user, mnt_drop_write(path.mnt); out_release: path_put(&path); + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } out: return error; } |